PC software toolkit speeds routine extrusion calculations.

For a long time, injection molders have benefited from software to help them with tasks ranging from mold-filling analysis to part costing. Extrusion processors, on the other hand, have had only their calculators and generic spreadsheets to rely on.

But now, Techware Designs of Youngstown, Ohio, the software subsidiary of Spirex Corp., has come out with "The Extruder's Technician" (or "ET") - a software package that performs numerous calculations common to extrusion operations. "Extrusion processors had been asking when we would create software for their needs," says Brad Smith, Techware's president.

Scheduled for release this month, ET (which was developed in cooperation with PLASTICS TECHNOLOGY) takes some cues from Techware's "Molder's Technician" software, which has sold over 100 copies since its release last year (see PT, Jan. '95, p. 21). Like its injection molding cousin, ET offers engineering calculations, reference guides, unit conversions, cost-estimating capabilities, and troubleshooting information. ET's features are customized for specific extrusion processes - including blown and cast film, wire and cable, pipe, profile, and sheet.

ET's user interface is built around a set of icons at the top of the screens. Clicking on any one of these summons drop-down menus and sub-menus from which users activate the software's features.

Users manually enter most of their extrusion data by filling in clearly marked input fields [ILLUSTRATION FOR PHOTOS OMITTED]. At the same time, ET's designers kept data-entry requirements to a minimum in two ways: First, information computed in one section of ET (e.g., extrudate cross-sectional area) can flow directly into another section where it's needed for a related calculation (e.g., product cost estimation). Second, if you're not sure what data to enter in a field, clicking on an adjacent "button" calls up a menu of typical entries for that field. You simply pick one that best matches your process or material. For example, one menu supplies melt-density values, which you won't find on a typical resin data sheet.

TIME-SAVING CALCULATIONS

ET's calculation programs let users quickly answer a number of extrusion-specific questions, including those related to pressure drop at the die and production rate. Other ET calculation programs automatically determine extrudate volumes, areas, lengths, and weights. ET also provides a host of generic engineering calculations covering mechanical, electrical, and statistical problems. There's even a function for conversions from English to metric units.

The screw throughput estimator stands out as a particular time saver, says Smith. This program estimates the extrusion rate for a given screw, material, and process conditions. ET can likewise forecast the throughput of a worn screw. "Extrusion processors always want to know what the payback from changing an old screw would be. This program will tell them," explains Smith.

HANDY REFERENCE GUIDES

ET's reference section pulls together a number of information resources, including the following:

* Resin data such as viscosities and drying conditions.

* Screw and barrel information such as alloy compatibilities, rebuilding points, and hard-facing material choices.

* Generic guides to electrical, mechanical, and chemical information.

The reference section also lets users create their own documents. For instance, ET's "set-up sheets" will store commonly used processing parameters by job number. Users can also build procedure manuals for start-ups, shutdowns, and process-monitoring tasks.

JOB-QUOTING ASSISTANCE

For estimating product costs, users input details on the material, product, and machine on which it will be produced. Specify a desired profit, and the program will recommend a price for the job.

Among the cost inputs, ET asks for the product dimensions, weight, and output rates - all of which can flow in from the package's other calculation programs. The pricing program also takes into account the following:

* Extruder-related costs such as machine-hour rates and set-up expenses.

* Material costs for one or more resins (the latter for coex applications).

* Secondary costs such as those associated with tooling, downstream equipment, and packaging.

Users can specify the units (e.g., feet, pounds) in which products sell.

TROUBLESHOOTING AND MORE

Troubleshooting features for specific extrusion processes match up common processing problems with likely causes and suggested solutions.

On-line help comes in two forms. One is an on-line manual to the entire ET package. The other is more context-specific - for instance, drop-down "windows" that define the variables used in a calculation. Techware provides service and support via a direct telephone number.

Expected price for ET is $895, which includes a year's worth of free upgrades.

RELATED ARTICLE: Computer Requirements

* IBM-compatible 386-based PC or better (a 486 is recommended).

* At least 4 MB of RAM (8 MB would be better).

* Microsoft Windows 3.1 or later.